JP2022135321A - Catalyst heating system - Google Patents

Abstract

To prevent a catalyst for purifying exhaust gas from being not heated appropriately.SOLUTION: A catalyst heating system S comprises: a push switch 8 that detects whether a wheel chock 9 is stored in a storage part 10 of a vehicle or the wheel chock 9 is taken out of the storage part 10; a heater 5 that heats a catalyst 4 for purifying vehicle exhaust gas to a temperature at which the catalyst 4 is activated; and a heating control unit 122 that activates the heater 5 when the push switch 8 detects that the wheel chock 9 is taken out of the storage part 10 and then that the wheel chock 9 is stored in the storage part 10.SELECTED DRAWING: Figure 1

Description

The present invention relates to a catalyst heating system for heating a catalyst that purifies exhaust gas.

In order to reduce harmful components contained in the exhaust gas, an exhaust gas purifying catalyst is provided in the exhaust pipe. Since the catalyst does not work unless it is heated to an activation temperature, Patent Literature 1 discloses a technique for starting heating the catalyst at the timing when the door of the vehicle is opened.

JP-A-5-202737

However, since the time from the opening of the door to the start of the engine is short, the temperature of the catalyst cannot be sufficiently raised to the temperature at which the catalyst is activated.

Accordingly, the present invention has been made in view of these points, and it is an object of the present invention to prevent the temperature of a catalyst that purifies exhaust gas from rising appropriately.

In an aspect of the present invention, a sensor for detecting whether a wheel chock is stored in a storage portion of a vehicle or whether the wheel chock is taken out from the storage portion, and a catalyst for purifying exhaust gas of the vehicle are provided in the catalyst. and a heater that heats to a temperature that activates and once the sensor detects that the spigot has been removed from the stowage and once the sensor has detected that the spigot has been retracted into the stowage and a heating control unit for operating the heater.

The catalyst heating system further includes a temperature acquisition unit that acquires the temperature of the catalyst, and the heating control unit controls the temperature acquisition unit when the sensor detects that the wheel clasp is stored in the storage unit. may operate the heater when the acquired temperature of the catalyst satisfies a condition that is less than a predetermined value lower than a temperature at which the catalyst is activated.

The catalyst heating system is configured to operate the catalyst heating system from the time of removal, when the sensor detects that the chock has been removed from the storage section, to the time of storage, when the sensor detects that the chock has been retracted into the storage section. The heating control unit further includes a usage time specifying unit that specifies the usage time during which the clasp is used, and the heating control unit, when the usage time specified by the usage time specifying unit satisfies a condition that the usage time is equal to or longer than a predetermined time. , the heater may be activated.

The catalyst heating system may further include a temperature acquisition unit that acquires the ambient temperature of the vehicle, and a predetermined time setting unit that sets the predetermined time longer as the ambient temperature acquired by the temperature acquisition unit is higher. good.

ADVANTAGE OF THE INVENTION According to this invention, it is effective in being able to suppress that the temperature of the catalyst which purifies exhaust gas is not raised appropriately.

It is a figure which shows the structure of a catalyst heating system. It is a schematic diagram which shows the state by which the wheel stopper is stored in the storage part. It is a schematic diagram which shows the state by which the clasp is taken out from the storage part. FIG. 4 is an operation sequence diagram of a push switch; 4 is a flow chart showing an example of the flow of processing executed by a heater control device;

[Configuration of catalyst heating system S]
FIG. 1 is a diagram showing the configuration of a catalyst heating system S. As shown in FIG. The catalyst heating system S is a system that heats the catalyst 4 that purifies the exhaust gas of the engine of a vehicle such as a truck. A catalyst heating system S includes a heater control device 1 , an engine 2 , an exhaust passage 3 , a catalyst 4 , a heater 5 , a catalyst temperature sensor 6 , an ambient temperature sensor 7 and a push switch 8 .

The engine 2 is an internal combustion engine that burns and expands a mixture of fuel and intake air (air) to generate power. The engine 2 according to this embodiment is a four-cylinder diesel engine. The engine 2 may be an engine other than four cylinders.

The exhaust passage 3 is an exhaust pipe connected to the engine 2 . The exhaust passage 3 discharges exhaust gas from the engine 2 to the outside of the vehicle. A catalyst 4 is provided in an exhaust passage 3 through which exhaust gas flows.

The catalyst 4 is a catalyst that purifies the exhaust gas of the vehicle. The catalyst 4 is, for example, a three-way catalyst. The catalyst 4 is activated to purify the exhaust gas when it reaches the activation temperature (for example, 200°C). Specifically, catalyst 4 oxidizes hydrocarbons to water and carbon dioxide, and carbon monoxide to carbon dioxide. The catalyst 4 also reduces nitrogen oxides to nitrogen. Note that the catalyst 4 is not limited to a three-way catalyst as long as it can purify the exhaust gas.

The heater 5 is arranged in contact with the surface of the catalyst 4 . The heater 5 generates heat when energized to heat the catalyst 4 . The heater 5 heats the catalyst 4 to an activation temperature at which the catalyst 4 is activated before the engine 2 is started. The activation temperature is, for example, 200°C. The heater 5 is, for example, a PTC (Positive Temperature Coefficient) heater, but is not limited to this.

The catalyst temperature sensor 6 is arranged upstream of the catalyst 4 . The catalyst temperature sensor 6 sequentially detects the catalyst temperature, which is the temperature of the catalyst 4 . Catalyst temperature sensor 6 is, for example, a thermocouple or a thermistor. The interval at which the catalyst temperature sensor 6 detects the catalyst temperature may be appropriately set. A specific value of the interval at which the catalyst temperature sensor 6 detects the catalyst temperature is, for example, 100 milliseconds.

The ambient temperature sensor 7 detects the ambient temperature (outside air temperature) of the vehicle. The ambient temperature sensor 7 is, for example, an intake air temperature sensor provided at the intake port of the engine. The intake air temperature sensor is, for example, a thermocouple or a thermistor. The ambient temperature sensor 7 is not limited to this, and may be any sensor that can detect the ambient temperature of the vehicle.

The push switch 8 is a sensor that outputs a signal when the switch of the push switch 8 is not pressed and stops outputting a signal when the switch is pressed. The push switch 8 is installed in a storage section that stores the wheel chocks of the vehicle. A push switch 8 detects whether the wheel chock is stored in the storage section of the vehicle or whether the wheel chock is removed from the storage section.

FIG. 2 is a schematic diagram showing a state in which the wheel clasp 9 is stored in the storage section 10. As shown in FIG. When the wheel chock 9 is stored in the storage portion 10 of the vehicle V as shown in FIG. 2, the push switch 8 is in a pressed state. The push switch 8 detects that the wheel clasp 9 is stored in the storage part 10 when the switch is pushed. The push switch 8 does not output a signal when detecting that the wheel clasp 9 is stored in the storage portion 10 .

FIG. 3 is a schematic diagram showing a state in which the ring clasp 9 is taken out from the storage section 10. As shown in FIG. The wheel chock 9 shown in FIG. When the clasp 9 is removed from the housing 10 as shown in FIG. 3, the push switch 8 is in a non-depressed state. The push switch 8 detects that the wheel clasp 9 has been removed from the housing 10 when the switch is not pushed. When the push switch 8 detects that the wheel clasp 9 has been taken out of the housing portion 10, it outputs a signal.

A heater control device 1 controls a heater 5 that heats a catalyst 4 . The heater control device 1 includes a storage section 11 and a control section 12 . The storage unit 11 is a storage medium including a ROM (Read Only Memory), a RAM (Random Access Memory), a hard disk, and the like. The storage unit 11 stores programs executed by the control unit 12 .

The control unit 12 is a computing resource including a processor such as a CPU (Central Processing Unit). By executing the programs stored in the storage unit 11 , the control unit 12 realizes functions as a temperature acquisition unit 121 , a heating control unit 122 , a use time determination unit 123 and a predetermined time setting unit 124 .

The temperature acquisition unit 121 acquires the catalyst temperature, which is the temperature of the catalyst 4 . The temperature acquisition unit 121 acquires the catalyst temperature from the catalyst temperature sensor 6 each time the catalyst temperature sensor 6 detects the catalyst temperature. Also, the temperature acquisition unit 121 acquires the ambient temperature. Specifically, the temperature acquisition unit 121 acquires the ambient temperature from the ambient temperature sensor 7 each time the ambient temperature sensor 7 detects the ambient temperature.

The heating control unit 122 activates the heater 5 when the wheel clasp 9 is stored in the storage unit 10 after the wheel clasp 9 is taken out from the storage unit 10 . The process of operating the heater 5 by the heating control unit 122 will be specifically described below.

The heating control unit 122 determines whether or not the wheel chock 9 has been removed from the storage unit 10 when the engine 2 stops. More specifically, the heating control section 122 determines whether or not the push switch 8 has detected that the wheel clasp 9 has been removed from the storage section 10 .

When the heating control unit 122 determines that the ring clasp 9 has been taken out of the storage unit 10 , it determines whether or not the ring clasp 9 has been stored in the storage unit 10 . Specifically, the heating control unit 122 determines whether or not the push switch 8 has detected that the wheel clasp 9 has been stored in the storage unit 10 . Then, when the heating control section 122 determines that the wheel clasp 9 is stored in the storage section 10 , it activates the heater 5 .

A driver who drives the vehicle V inspects the vehicle V after storing the wheel chock 9 in the storage part 10 and before opening the door of the vehicle V and getting into the vehicle V. - 特許庁Therefore, it takes time for the driver to inspect the vehicle V from when the wheel chock 9 is stored in the storage portion 10 until the door of the vehicle V is opened. Therefore, the heating control unit 122 heats the catalyst 4 for a longer time by activating the heater 5 at the timing when the wheel stopper 9 is stored in the storage unit 10 than when the heater 5 is activated at the timing when the door is opened. can continue. As a result, the temperature of the catalyst 4 is sufficiently increased by being heated for a long time before the engine 2 is started, so the heating control unit 122 prevents the catalyst 4 that purifies the exhaust gas from being appropriately heated. can.

The heating control unit 122 may operate the heater 5 when the catalyst temperature is less than a predetermined value when the removed wheel clasp 9 is stored in the storage unit 10 . In this case, the heating control unit 122 determines whether or not the catalyst temperature acquired when the push switch 8 detects that the wheel clasp 9 is stored in the storage unit 10 is less than a predetermined value lower than the catalyst temperature. . The predetermined value is, for example, a temperature at which the catalyst 4 can exhibit 80% or more of the purification performance. A specific value of the predetermined value is 150°C when the activation temperature is 200°C. The heating control unit 122 operates the heater 5 when determining that the catalyst temperature is less than the predetermined value. The heating control unit 122 does not operate the heater 5 when determining that the catalyst temperature is equal to or higher than the predetermined value.

By doing so, the heating control unit 122 does not operate the heater 5 when the catalyst temperature is high, and operates the heater 5 only when the catalyst temperature is low. Therefore, the heating control unit 122 can suppress the operation of the heater 5 when the catalyst temperature is high, thereby suppressing unnecessary power consumption.

If the use time of the wheel clasp 9 is long, it is considered that the catalyst temperature has decreased. Therefore, the heating control unit 122 operates the heater 5 when the taken-out wheel clasp 9 is stored in the storage unit 10 and the usage time of the wheel clasp 9 is equal to or longer than the judgment time. Let In this case, the usage time identification unit 123 identifies the usage time during which the clasp 9 is used. FIG. 4 is an operation sequence diagram of the push switch 8. As shown in FIG. The horizontal axis of FIG. 4 indicates time t.

The usage time specifying unit 123 specifies the time when the wheel chock 9 is taken out from the storage unit 10 . Specifically, the usage time specifying unit 123 specifies the time t0 at which the push switch 8 detects that the wheel clasp 9 has been taken out of the storage unit 10 as the take-out time. Subsequently, the use time specifying unit 123 specifies the storage time point when the wheel clasp 9 is stored in the storage unit 10 . Specifically, the usage time specifying unit 123 specifies the time t1 at which the push switch 8 detects that the wheel clasp 9 has been stored in the storage unit 10 as the storing time. Then, the usage time specifying unit 123 specifies the usage time D from the time of taking out to the time of storing.

Predetermined time setting unit 124 sets a determination time for determining whether or not the catalyst temperature has decreased based on the length of usage time. For example, the higher the ambient temperature, the less the catalyst temperature decreases, so the predetermined time setting unit 124 sets the predetermined time longer as the ambient temperature is higher. A specific value of the predetermined time is, for example, 5 minutes.

After the use time specifying unit 123 specifies the use time D, the heating control unit 122 determines whether or not the use time D is equal to or longer than a predetermined time. The heating control unit 122 activates the heater 5 when determining that the specified usage time D is equal to or longer than the predetermined time. The heating control unit 122 does not operate the heater 5 when determining that the usage time D is less than the predetermined time. By doing so, the heating control unit 122 can operate the heater 5 when the usage time D of the wheel clasp 9 is long and the catalyst temperature is lowered. Further, the heating control unit 122 does not operate the heater 5 when the use time D of the wheel clasp 9 is short and the catalyst temperature is high, so unnecessary power consumption can be suppressed.

[Flow of Processing Executed by Heater Control Device 1]
FIG. 5 is a flow chart showing an example of the flow of processing executed by the heater control device 1. As shown in FIG. The flowchart of FIG. 5 is executed when the engine 2 stops.

First, the heating control section 122 determines whether or not the wheel clasp 9 has been removed from the storage section 10 (step S1). Specifically, the heating control unit 122 determines whether or not the push switch 8 has detected that the wheel clasp 9 has been removed from the storage unit 10 .

When the wheel chock 9 has not been removed from the storage section 10 (No in step S1), the heating control section 122 determines whether or not the engine 2 has started (step S2). When the engine 2 has not started (No in step S2), the heating control unit 122 returns to step S1. When the engine 2 has started (Yes in step S2), the heating control unit 122 ends the process. In this manner, the heating control section 122 terminates the process if the wheel chock 9 is not removed from the storage section 10 even when the engine 2 is stopped. Therefore, the heating control unit 122 can prevent the heater 5 from operating when the engine 2 is stopped due to idling stop or the like.

When the ring clasp 9 has been taken out of the storage section 10 (Yes in step S1), the heating control section 122 determines whether or not the ring clasp 9 has been stored in the storage section 10 (step S3). Specifically, the heating control unit 122 determines whether or not the push switch 8 has detected that the wheel clasp 9 has been stored in the storage unit 10 . If the ring clasp 9 is not stored in the storage unit 10 (No in step S<b>3 ), the heating control unit 122 waits until the ring clasp 9 is stored in the storage unit 10 .

When the wheel stopper 9 is stored in the storage unit 10 (Yes in step S3), the temperature acquisition unit 121 acquires the catalyst temperature (step S4). Specifically, the temperature acquisition unit 121 acquires the catalyst temperature when the push switch 8 detects that the wheel clasp 9 is stored in the storage unit 10 .

The heating control unit 122 determines whether or not the catalyst temperature is less than a predetermined value (step S5). If the catalyst temperature is equal to or higher than the predetermined value (No in step S5), the heating control unit 122 ends the process without operating the heater 5. When the catalyst temperature is less than the predetermined value (Yes in step S5), the heating control unit 122 activates the heater 5 (step S6).

(Modification)
In the above embodiment, heater 5 directly heated catalyst 4 . Alternatively, the catalyst heating system S may heat the catalyst 4 by causing air heated by a heater (hot air) to flow into the exhaust passage 3 using an electric supercharger.

[Effect of heater control device 1]
As described above, the heater control device 1 activates the heater 5 when the wheel clasp 9 is stored in the storage part 10 after the wheel clasp 9 is taken out from the storage part 10 . It takes time for the driver to check the vehicle V from when the wheel chock 9 is stored in the storage part 10 until the door of the vehicle V is opened. Therefore, the heater control device 1 activates the heater 5 at the timing when the wheel stopper 9 is stored in the storage portion 10, so that the heater 5 is operated for a longer time than when the heater 5 is activated at the timing when the door of the vehicle V is opened. 4 can continue to be heated. As a result, the catalyst 4 is heated for a long period of time to raise its temperature to the activation temperature, so that the heater control device 1 can prevent the catalyst 4 for purifying the exhaust gas from being heated appropriately.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of the gist thereof. be. For example, all or part of the device can be functionally or physically distributed and integrated in arbitrary units. In addition, new embodiments resulting from arbitrary combinations of multiple embodiments are also included in the embodiments of the present invention. The effect of the new embodiment caused by the combination has the effect of the original embodiment.

S catalyst heating system 1 heater control device 11 storage unit 12 control unit 121 temperature acquisition unit 122 heating control unit 123 usage time identification unit 124 predetermined time setting unit 2 engine 3 exhaust passage 4 catalyst 5 heater 6 catalyst temperature sensor 7 ambient temperature sensor 8 Push switch 9 Wheel stopper 10 Storage part V Vehicle

Claims (4)

a sensor for detecting whether the wheel chock is stored in a storage compartment of the vehicle or whether the wheel chock has been removed from the storage compartment;
a heater for heating a catalyst for purifying the exhaust gas of the vehicle to a temperature at which the catalyst is activated;
a heating control unit that activates the heater when the sensor detects that the spigot has been taken out of the storage unit and then that the spigot has been stored in the storage unit;
a catalytic heating system having a further comprising a temperature acquisition unit that acquires the temperature of the catalyst,
The heating control unit is configured such that the temperature of the catalyst acquired by the temperature acquiring unit when the sensor detects that the wheel stopper is stored in the storage unit is a predetermined temperature lower than a temperature at which the catalyst is activated. activating the heater if the condition of being less than a value is met;
2. The catalytic heating system of claim 1. The clasp was used from the time of removal when the sensor detected that the chock was removed from the storage compartment to the time of retraction when the sensor detected that the chock was retracted into the storage compartment. further comprising a usage time identification unit that identifies the usage time,
The heating control unit operates the heater when the usage time specified by the usage time specifying unit satisfies a condition that the usage time is equal to or longer than a predetermined time.
2. The catalytic heating system of claim 1. a temperature acquisition unit that acquires the ambient temperature of the vehicle;
a predetermined time setting unit that sets the predetermined time longer as the ambient temperature acquired by the temperature acquisition unit is higher;
4. The catalytic heating system of claim 3.

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